Tire tread and apparatus for forming same



Jan. 19, 1954 H. E. KlMl-:s 2,666,470

TIRE TREAD AND APPARATUS F' OR FORMING SAME Filed Aug. 27, 1949 2 Sheets-Sheet 2 F f E. 8. F E. 9., v

Zu/nforx L/farold E .fz'mes Patented Jan. 19, 1954 rffi.

TIRE TREADAND APPARATUS FOB- FORMING SAME Harold E. Kimes, Chicago, Ill., assignor to Harold E. Kimes Corporation? Chicago, Ill., aV corporation of Illinois v, V

'b Application August 27, 194'9, serial No. 112,711

This invention relates to improvements in the tread portion of pneumatic tire casings and to apparatus for forming same. I

This invention is more particularly concerned with the provision of a tread portion of a pneumatic tire casing embodying a plurality of metallic inserts formed and arranged to prevent punctures and skidding during use of the tire casing. Metallic inserts of the type hereinafter shown and ,described in connection with the present invention are shown and described in my co-pending patent application filed December 21, 1948, Serial No. 66,437,V which has matured into PatentV No. 2,600,506, patented June 117, 1952.

The xpresent invention contemplates the provision of a tire tread embodying a plurality of U or W-shaped Vmetallic insertsV comprising a curvilinear base and a pair of arcuate arms extending radially and'terminating at the outer surface of the treadl to provide sharp ngers adapted to engage the surface of a road. The metallic inserts may be' in the form of individual U-shaped membersflor'may be in the form of a continuous chain of U-'shaped members connected' together at the outer ends of their arms.

This invention further contemplates the pro-` vision of means for mounting a chain of connected metallic inserts in proper alignment within a tire mold during molding `of a tire tread. j

This invention further contemplates the provision of guide andretaining means for positioning and holding metallic inserts in position within standard types of tire molds. This is accomplished by providing a matrix plate within the mold cavity to position the metallic inserts and by employing the use of metallic clips to secure the metallic inserts to the matrix plate. In. one form of the invention hereinafter set forth, the matrix plate is secured within, the mold cavity by means ,of screws, xbolts or the like for use in successive tread molding operations. In another form of the invention hereinafter set forth the matrix plate serves to hold a group of individual inserts in predetermined spaced arrangement during the molding operation and is thereafter Vstripped from the tire tread and discarded. i

This invention further* contemplates the provision of a matrix plate adapted for use in tire mold cavities of different shapes.

This invention embodies other novel features. details of construction and 'arrangement of parts which are hereinafter'set forth in the specification. nd claims, Vand illustrated in the accompaiiying drawings. wherein:

' 12'Claims. (Cl.152-211) Fig. 1 is a fragmentary transverse sectional view illustrating the manner in which the metallic inserts are mounted and secured to matrix plates provided within the cavities of a clam-type tire mold.

Fig. 2 is a fragmentary plan view illustrating one type of matrix plate.

Fig. 3 is a fragmentary plan view illustrating the type of matrix plate provided within the central cavity of aV Clam-type tire mold.

Fig. 4 is a fragmentary sectional view illustrating the contour of a finished tiretread and the manner in which a metallic insert and looking clip are arranged therein.

Fig. 5 is a fragmentary sectional view illustrating the manner in which some of the openings in the matrix plate are filled with rubber plugs prior to the molding operation.

Fig. 6 is a perspective view illustrating a rubber plug of the type adapted for use in filling open holes in the matrix plate.

Fig. 7 is a detail view illustrating the type of clip employed for securing the metallic inserts to the matrix plates. 1

Fig. 8 is a fragmentary transverse sectional view of a tire mold illustrating a modified form` of matrix plate.

Fig. 9 is a fragmentary sectional view, corresponding to Fig. 8, showing the `'means employed for securing the matrix plate to the tire mold.

Fig. 10 is a fragmentary detail plan view illustrating the construction of the matrix plate shown in Figs. 8 and 9.

Fig. 11 is a fragmentary view of the interior of a tire mold cavity illustrating the manner in which a matrix plate may be formed to suit the contour of a different mold cavity.

Fig. 12 is a fragmentary plan view illustratingwhen the latter is separated from the mold and matrix plate illustrated in Fig. 13.

Fig. 15 is a fragmentary sectional view taken along the line 15-15 of Fig. 14.

Referring now to the drawings for a better understanding of this invention, and more particu-l matrix plates are each providedwithiafseriesaofi L apertures |6 disposed at spaced intervalsflo the longitudinal axis of the late to,re `ceiy,e ,the, mounting screws |2 and reta a clipsfilli-j1fn x1fef sired, the holes for the mounting screws T 2"ii1"a`y` be provided along one or bothflflanges l'4-l4 of the matrix piates n, as indicatdi'xt milih-'Figfs:b

of the drawings. In alam-type molds, itiswontemplated that the matrix plates l l shallhextei'fd4 n er5 illustrated inlFig. luf'of Vthe vdraiiriii'Sy @The V 'om hardened to pig e'rvialiieendimexi 311911? :maesjuri ea; Wheaiire,,cesingeembdytallic insert a re .iproyi'ded v for. CQIitemPlat dithali'lh @lain @f masih? foflrmedrfren' brbtlizve wire or from any metallic alloy whichrwill ,reduce earkina--:duringafriiiqnal:fensaeemt of 'the clips against'a hi trd-surf acedroad.b I

inserts 185 humervesto: pi peny position. each. o f V.the W-shaped c1ips:-;2=.|...`1n;.pr9per.nositi0n Witlimits .wiresclipa..v llzformed; fromlerieths;`v of., Wirebent intermediate their ends tofpr, portions. 26;+=26;5 and a, connecting. .1099;130 .V

21. The Outer. endsofithelegsiiZfifZ fiare .Crimped at izflato:proyideishoulders..adaptedto frictionallx:

engage.`` the marginal .fedges ,of their 1 respectiye;V

Each matrix plate comprises a concave; 1,.

molding operation. As the molding of tire treads on pneumatic tire casings is well known in this art, a description of the molding operation has been omitted.

Fig. 4 in the drawings illustrates a section of a moldedtire tread embodyingachainof metallic inserts 19 (e-fclipsii'il'l, .lit vWill hegrioted that the 'oiit'rlsurfce "of the 'trettd'section is formed r `With a concave annular recess 32 and side shoullo'de'rs 33- 33. During the operation of this type i oftiremtreadfinja vehicle, it will be noted that .fth'e'sh'oulder portions 33--33 will be compressed duringiengagement against the surface of a road V'La `w`1''c'y thege'nds of the legs 23-23 of f5 the p 'f2l to be pressed into engagement against thero'ad surface. It is, of course, -`desirable thatrechAN-shaped clip shall be separatedfrom its adjacent clips immediately upon u'e'lif'tlie tire casing. .,The immediate separa- 20 tign ofthe clips 21 from adjacent clipsY during operation jofithei'tire'casingf*may 'bel accomplished by 'partially severirigftl'ie Wire: at' the Vpoints'hf juncturezllV o f ,connected clips-,"or hy` flattenin'g the` junc't'ur'epoint 23415 of connected clips, VW'or; loy 2'5 crystallizingthemet `tptheiiuncture"illfof connected fclips 'duringft ehardening operation. fIt isfi'niportant that'th'e--` clip'sfZl shallhe broken 'order to preventjheating due "t'oss'andfissfwfredfin 65., tnegjuiictiires 'gaiibtiiieen fadiadeiifi ,'eiipsf 2 gj are prei amy. .,byfiiairtially, icutting'tnrougn thewire' at'th'se'tpzoi'fits', 'or' byfl'attening p ture points, order that the ch'am of conn ted mistis. Seal 70:` separate clips 2 I'f t z @SS-313344 strip jldis 751 metal having apertures side.

on' Between the clips fandlL the ruhityj by, 'means 4 of cap vcli'ain'fof insert's: tourjof' the imatrixiplate' 'asmara edges-tojreceive the ends ofjthe legs 48-4l l,; of individual W-shaped resilient wireV clips 49.;1'Ifhe individual Aclips lleare adapted vto bemounted upon the fiexible matrix strip 46 during manufacture of the clips. The matrix strip 46 with the clips 49 mounted thereonwis Vsold to manufacturers of new tires or to retreading plants where the strip of clips are 'mounted within a mold cavity in the manner iliustrated vinV Fig. 13. After the tire tread has been molded onto a tire casing, with the clips 49 imbedded within the tread, the matrix strip 46 is then manually stripped from the outer surface of the tread. Fig. illustrates the appearance of the tread of a tire after the matrix strip 46 has been removed therefrom. Fig. 14 illustrates the manner in which the clips 49 are arranged in spaced parallel relation within the annular bead of a tire tread. In the manufacture of the matrix strip 46 and clips 49, it is contemplated that the ends of the legs 48 may be pressed through the thin material forming the strip 46. To prevent accidental displacement of the clips from the strip 46, the legs 48 of each clip may be adhesively united to the strip adjacent the apertures 41. In this form of the invention the matrix strip 45 serves to hold the clips 49 in predet'ermined spaced relation for shipment and storage to the users and also serves to maintain the clips 49 in proper position within a mold cavity during the molding operation. In this form of the invention it will also be noted that the ends of the clips 49 project beyond the outer surface of the tire tread for frictional engagement with a road surface.

While this invention has been shown in several forms, it is obvious to those skilled in the art that it is not so limited but is susceptible of various changes and modifications Without departing from the spirit and scope of the claimed invention.

I claim as my invention:

l. In a pneumatic tire, an annular resilient rubber tread, a plurality of resilient metallic wire inserts embedded crosswise within said tread, said inserts ,having resilient arcuate arms projecting outwardly in spaced relation toward and terminating adjacent the outer surface of said tread, the outer surface of said tread being formed with a circumferentially extending concave recess disposed between the arms of said inserts.

2. In a pneumatic tire, an annular resilient rubber tread, a chain of connected resilient metallic wire inserts embedded crosswise within said tread, said inserts having resilient arcuate g bedded within said tread, said inserts having resilient'arcuate arms projecting outwardly toward and terminating beyond the outer surface of Vsaid tread, the outer surface of said tread being formed with a continuous concave recess disposed between the arms of said inserts.

4. An article of manufacture for use in the molding of anti-skid treads on tires comprising,

a strip of fiexible material suitable for use as a y matrix within a tire mold, and a plurality of generally U-shaped metallic inserts detachably secured in spaced relation along one side of said strip.

5:. A An V article ,of manufacture for; use inV the molding of anti-skid treads Von tires comprising, a strip offiexiblematerial suitable for use as a matrix within a tire mold, and a plurality of generally. `Ulu-shaped metallic inserts detachably secured in spaced relation along one side of 'said strip, the medial portion of said strip being concavo-convex in cross-sectionfito form an annular concave recess within the tread of a tire.

`6, An article of manufacture for use in the molding of anti-skid treads on tires comprising, a strip of fiexible material suitable for use as a matrix within a tire mold, and a plurality of generally U-shaped metallic inserts having the ends of their legs detachably secured to said strip.

'7. An article of manufacture for use in the molding of anti-skid treads on tires comprising, a strip of fiexible material suitable for use as a Vmatrix within a tire mold, and a plurality of generally U-shaped metallic inserts having the ends of their legs detachably secured to said strip, said inserts being disposed in spaced parallel relation.

8. An article of manufacture for use in the molding of anti-skid treads on tires comprising, a strip of fiexible material suitable for use as a matrix within a tire mold, and a plurality of generally U-shaped metallic inserts having the ends of their legs detachably secured to said strip, said inserts being disposed in spaced parallel relation transversely of the strip.

9. An article of manufacture for use in the molding of anti-skid treads on tires comprising, a strip of fiexible material suitable for use as a matrix within a tire mold, and a plurality of generally U-shaped metallic inserts having the ends of their legs detachably secured to said strip, said inserts being disposed in spaced parallel relation transversely of the strip, the ends of the legs of the metallic inserts'being secured within apertures formed in said strip.

10. A mold for applying rib treads to pneumatic tires, said ribs having imbedded therein circumferentially-extended wire elements bent to provide connected parallel rows of spaced radially outwardly-projecting friction members, said mold comprising 'a plurality of radially inWardly-projecting endless parallel tread design-forming flanges, andan endless radially inwardly-proj ecting wire element-centering rib intermediate said flanges, said rib having a height less than said fianges and a width less than the space between said fianges.

11. In a pneumatic tire, an annular resilient rubber tread, a plurality of inserts formed of resilient metallic wire embedded transversely within said tread, each of said inserts being generally U-shape to provide a base and a pair of spaced legs projectlng outwardly from the base and converging toward and terminatmg adla- V cent the outer surface of said tread, the outer surface of said tread being formed with a circumferentially extending recess disposed between the legs of said inserts.

12. In a pneumatic tire, an annular resilient rubber tread, a cham of connected inserts formed of resilient metallic wire embedded transversely within said tread, each of said inserts being generally U-shape to provide a base and a pair of spaced legs projecting outwardly from the base and converging toward and terminating adjacent the outer surface of said tread, the outer surface of said tread being formed with a circum- 

